ARM: gpio: consolidate trivial gpiolib implementations

Consolidate 24 trivial gpiolib implementions out of mach/gpio.h
into asm/gpio.h.  This is basically the include of asm-generic/gpio.h
and the definition of gpio_get_value, gpio_set_value, and gpio_cansleep
as described in Documentation/gpio.txt

Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Tested-by: David Brown <davidb@codeaurora.org>
Acked-by: David Brown <davidb@codeaurora.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:
	arch/arm/mach-tegra/include/mach/gpio.h